Earthquake near San Juan Bautista, CA

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 15 km (9 mi) from the epicentre. In San Juan Bautista, 5 km away, the estimate is intensity II (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

Likely felt in: Prunedale 12 km, intensity II · Hollister 14 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 38 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

1. Mineral, Virginia 2011 M 5.8 390,000× the energy of this one
2. Magna, Utah 2020 M 5.7 280,000× the energy of this one
3. Around the size people start to feel M 3.0 25× the energy of this one
4. This earthquake M 2.1 about 38 lb of TNT

Energy from the Gutenberg–Richter relation (log₁₀E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.

For this area

The largest earthquake within 50 km since 2016 was M 4.7 on 2019-10-15 — about 9,100 times the energy of this one.

Before 2016, the USGS record lists 28 earthquakes of M5 or more within 50 km; the five largest:

1. 6.9 The 1989 Loma Prieta, California Earthquake · 40 km NW of this epicentre Oct 18, 1989
2. 6.5 Near Morgan Hill, California · 35 km NNW of this epicentre Jul 1, 1911
3. 6.1 Near San Jose, California · 50 km NNW of this epicentre Jun 11, 1903
4. 5.9 10 km SE of Tres Pinos, California · 29 km ESE of this epicentre Apr 9, 1961
5. 5.8 Near Watsonville, California · 22 km NW of this epicentre Mar 11, 1910

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 36.8022, -121.5407. Map © OpenStreetMap contributors.

Nearby places

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

52 earthquakes have been recorded within 50 km since this one.

1. 2.2 4km ENE of Pinnacles, CA 01:32 UTC
2. 1.8 3km NNW of Pinnacles, CA 18:24 UTC
3. 2.2 2km W of Tres Pinos, CA 06:24 UTC
4. 2.5 3km WSW of San Juan Bautista, CA 12:48 UTC
5. 2.6 3km NNW of Pinnacles, CA 21:13 UTC
6. 1.7 2km ENE of Aromas, CA 18:18 UTC
7. 1.6 6km SW of Ridgemark, CA 06:34 UTC
8. 1.8 9km ENE of Morgan Hill, CA 18:27 UTC
9. 1.8 4km NNE of Pinnacles, CA 07:28 UTC
10. 2.1 8km SSW of Tres Pinos, CA 01:46 UTC
11. 1.9 4km NNE of Pinnacles, CA 09:10 UTC
12. 2.4 4km NNE of Pinnacles, CA 08:15 UTC
13. 1.9 4km NNE of Pinnacles, CA 22:08 UTC
14. 1.8 5km NNE of Pinnacles, CA 21:27 UTC
15. 2.0 5km NNE of Pinnacles, CA 20:36 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 08:06 UTC. QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

On USGS

• The official USGS event page — the source of record for every value above
• Did you feel it? Report it to USGS — reports go to USGS, not to us
• ShakeMap for this event, when USGS has produced one

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.